Current concepts of anatomy and electrophysiology of the sinus node.

The sinoatrial node, or sinus node, of humans is the principal pacemaker of the heart. Over the last century, studies have unraveled the complex molecular architecture of the sinus node and the expression of unique ion channels within its specialized myocytes. Aim of this review is to describe the embriology, the anatomy, the histology and the electrophisiology of the sinus node.